[PATCH iproute2 v2] Add "show" subcommand to "ip fou"

[PATCH iproute2 v2] Add "show" subcommand to "ip fou"

[Greg Greenway]

Sample output:

$ sudo ./ip/ip fou add port 111 ipproto 11
$ sudo ./ip/ip fou add port 222 ipproto 22 -6
$ ./ip/ip fou show
port 222 ipproto 22 -6
port 111 ipproto 11

Signed-off-by: Greg Greenway <ggreenway@apple.com>
---
 ip/ipfou.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/ip/ipfou.c b/ip/ipfou.c
index 00dbe15..ecbaf11 100644
--- a/ip/ipfou.c
+++ b/ip/ipfou.c
@@ -28,6 +28,7 @@ static void usage(void)
 	fprintf(stderr, "Usage: ip fou add port PORT "
 		"{ ipproto PROTO  | gue } [ -6 ]\n");
 	fprintf(stderr, "       ip fou del port PORT [ -6 ]\n");
+	fprintf(stderr, "       ip fou show\n");
 	fprintf(stderr, "\n");
 	fprintf(stderr, "Where: PROTO { ipproto-name | 1..255 }\n");
 	fprintf(stderr, "       PORT { 1..65535 }\n");
@@ -134,6 +135,63 @@ static int do_del(int argc, char **argv)
 	return 0;
 }
 
+static int print_fou_mapping(const struct sockaddr_nl *who,
+				 struct nlmsghdr *n, void *arg)
+{
+	FILE *fp = (FILE *)arg;
+	struct genlmsghdr *ghdr;
+	struct rtattr *tb[FOU_ATTR_MAX + 1];
+	int len = n->nlmsg_len;
+	unsigned family;
+
+	if (n->nlmsg_type != genl_family)
+		return 0;
+
+	len -= NLMSG_LENGTH(GENL_HDRLEN);
+	if (len < 0)
+		return -1;
+
+	ghdr = NLMSG_DATA(n);
+	parse_rtattr(tb, FOU_ATTR_MAX, (void *) ghdr + GENL_HDRLEN, len);
+
+	if (tb[FOU_ATTR_PORT])
+		fprintf(fp, "port %u", ntohs(rta_getattr_u16(tb[FOU_ATTR_PORT])));
+	if (tb[FOU_ATTR_TYPE] && rta_getattr_u8(tb[FOU_ATTR_TYPE]) == FOU_ENCAP_GUE)
+		fprintf(fp, " gue");
+	else if (tb[FOU_ATTR_IPPROTO])
+		fprintf(fp, " ipproto %u", rta_getattr_u8(tb[FOU_ATTR_IPPROTO]));
+	if (tb[FOU_ATTR_AF]) {
+		family = rta_getattr_u8(tb[FOU_ATTR_AF]);
+		if (family == AF_INET6)
+			fprintf(fp, " -6");
+	}
+	fprintf(fp, "\n");
+
+	return 0;
+}
+
+static int do_show(int argc, char **argv)
+{
+	FOU_REQUEST(req, 4096, FOU_CMD_GET, NLM_F_REQUEST | NLM_F_DUMP);
+
+	if (argc > 0) {
+		fprintf(stderr, "\"ip fou show\" does not take any arguments.\n");
+		return -1;
+	}
+
+	if (rtnl_send(&genl_rth, &req.n, req.n.nlmsg_len) < 0) {
+		perror("Cannot send show request");
+		exit(1);
+	}
+
+	if (rtnl_dump_filter(&genl_rth, print_fou_mapping, stdout) < 0) {
+		fprintf(stderr, "Dump terminated\n");
+		return 1;
+	}
+
+	return 0;
+}
+
 int do_ipfou(int argc, char **argv)
 {
 	if (argc < 1)
@@ -149,6 +207,8 @@ int do_ipfou(int argc, char **argv)
 		return do_add(argc-1, argv+1);
 	if (matches(*argv, "delete") == 0)
 		return do_del(argc-1, argv+1);
+	if (matches(*argv, "show") == 0)
+		return do_show(argc-1, argv+1);
 	fprintf(stderr, "Command \"%s\" is unknown, try \"ip fou help\".\n", *argv);
 	exit(-1);
 }
-- 
2.7.4

Re: [PATCH iproute2 v2] Add "show" subcommand to "ip fou"

[Stephen Hemminger]

On Thu, 16 Nov 2017 16:53:22 -0800
Greg Greenway <ggreenway@apple.com> wrote:

> Sample output:
> 
> $ sudo ./ip/ip fou add port 111 ipproto 11
> $ sudo ./ip/ip fou add port 222 ipproto 22 -6
> $ ./ip/ip fou show
> port 222 ipproto 22 -6
> port 111 ipproto 11
> 
> Signed-off-by: Greg Greenway <ggreenway@apple.com>

Applied, thanks. Sorry for the annoying procedural problem.